


Underbody

by brocon



Category: Hunter X Hunter
Genre: Blood, Dirty Talk, Light Sadism, M/M, Probably ooc, Sibling Incest, Sleep Deprivation, Sleep Sex
Language: English
Status: Completed
Published: 2018-04-16
Updated: 2018-04-16
Packaged: 2019-04-23 20:32:27
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Underage
Chapters: 1
Words: 3,054
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14340372
Author URL: https://archiveofourown.org/users/brocon/pseuds/brocon
Summary: Killua is sixteen, and his relationship with Illumi has changed a lot. But some things in their history keep repeating, no matter how many beasts named guilt wrap around them.Killua winds up in his bed again, but something has shifted in their dynamic.





	Underbody

Killua was sixteen years old, a whopping 5’5’’ with toned and hardened muscle stretching from his broadened shoulders to his sinewy calves and ankles. He was sprawled out, naked and aching on the silken sheets that had been their battleground. One of his feet was beginning to lose circulation because it was wrapped so tightly in the dark gray snake of a bedsheet. But he didn’t reach down to untangle it; that was the least of his worries. He could already see his skin breaking out in bruises, welts, and hickeys. There was no way he could hide all of these this time.

Killua groaned, flipping onto his side, letting the guilt wrap around him tighter than the bedsheet. He was way too old to still be crawling into his brother’s bed. Speaking of his devil in the desert—Illumi was laying on his back with his eyes closed, his breathing indicating he was still awake, and his hair a starburst of black tendrils beneath him. He had even more damage on him, as usual; but he would just stick some pins in his flesh to even out the teeth and claw marks, reverting his skin to its usual, inordinate clarity. Something about that thought made Killua angry. He had to walk out of this room nicked, fucked, and sore, but Illumi got to erase every inch of dirty secret Killua had carved into his skin.

How did he always get into the same mess over and over? There was no needle, torture, or conditioning to blame this on. This bed he’d been in countless times throughout his life was like a second home—it felt more like a home than his own bedroom did. Half of the bodily fluids that may have bypassed the sheets and embedded in this mattress were his. All of the bodily fluids embedded in Illumi were his. He looked over each inch of Illumi’s skin, tracing the events of the night from the moment he caught Illumi looking at him with clouded-over lust, to him nearly ripping Illumi’s clothes off in the hallway to punish that perverse behavior, to Illumi dutifully riding him, hair falling on Killua like the thin veil of venom he’d spit during each thrust. He called Illumi a brother-fucker, whore, pervert—every insult that Illumi’s insides didn’t suck out of his vocabulary.

“Illumi.” Killua’s voice sounded as though it had been stripped bare with sandpaper. Maybe he’d been screaming insults louder than he thought. Illumi opened his eyes slowly, the creases erupting at the corners said he was exhausted. Killua rarely saw him look this tired—but he _had_ intercepted him after he had gotten home from a long job. Illumi had been so shocked to see Killua standing in their home that he’d dropped his overnight bag, and it never got picked up from the middle of the hallway. Killua was just visiting for Kalluto’s birthday, which reminded him of how he’d spent all night nailing their older brother. Killua was a terrible big brother, but it definitely ran in the family.

When Illumi didn’t say anything, Killua placed a hand on the broad expanse of his chest and laid his head on Illumi’s outstretched bicep. He could hear Illumi’s pulse quicken immediately beneath his soothingly-cool skin. Even when Illumi had been nearly drowned and pumped full of poison while hooked to an EKG his pulse barely budged. Killua exclusively held the keys to one of Illumi’s only weaknesses, because he was the weakness. “Don’t fix your skin this time.”

The deep shadows that were Illumi’s eyes wandered over to him, as if trying to figure out what kind of test or game this was. It was always a test or game with him. “You know that won’t do, Killu.”

Before his tired mind could catch up with his body, he was raking his claws across Illumi’s sternum, blood rising up to meet his nails like he’d slung paint across Illumi’s body. “Bastard. Hypocrite. Coward.”

Illumi turned onto his side, and Killua wondered how he never pulled his own hair by laying on it. The blood trickled down the side of his chest, racing to meet the rest of their bodily fluids on the filthy sheets. His face was less than an inch away from Killua’s now, their noses almost touching. “You’re beautiful, Killu.”

The bastard knew how to play the game. Killua was a sucker for compliments, especially from a man who gave compliments to no one else on the planet. He wondered if Illumi really meant it, but it didn’t matter as long as it sent pleasant waves through Killua’s spine from just hearing it. “Say it again.”

Illumi wrapped his arm around the small of Killua’s back, pulling their bodies flush against each other. The blood from Illumi’s chest pressed to Killua, leaving a bloody impression like a stamp. “Beautiful,” he mumbled now, as if he were starting to fall asleep as he spoke. Killua had to strain to hear him say, “Ethereal, flawless, powerful, blue, always—” He was getting incoherent, drifting off to a scenario even more ideal than the one he was in now. Killua was the perfect little heir in Illumi’s dreams, sitting on their father’s throne with the eyes of a hardened killer and the confidence of a king, instead of a teen who still needed petty compliments to inflate him.

But Killua wasn’t done with him right here and now.

“Illumi,” he said, bringing a hand up and burying it in the depths of Illumi’s hair. “I’m going to leave here and go fuck Hisoka.”

The reaction was satisfyingly predictable, Illumi’s eyes and face screwing up into a void with a burst of unrestrained nen, bloodlust filling the entire room. His hair rose from the bed like each strand was individually possessed by a demon, Killua’s hand caught up in the torrent of nen and hair. It burnt Killua’s body just to be near him.

Killua smiled, flashing his teeth and catching his blue eyes in the light of the morning pouring through the window. Illumi came down as quickly as he rose, like a disappointed dick on an otherwise magical wedding night. Strung out, confused, and barely-conscious as he tried to process the reason Killua had riled him up. Shame flashed in his face as he realized he’d let slip such an irresponsible release of nen in the house and that there was a large chance it had been sensed by their parents—or someone who would let their parents know promptly.

He felt powerful for being able to do this to Illumi. Even though he was sixteen, he still wasn’t over these quiet games of revenge in his head. Revenge for the conditioning, control, and torture. Even though he mostly understood the reasons for it now, he felt a rush every time he had the slightest bit of control. Maybe he would deprive Illumi of sleep more often.

He felt himself getting hard again at the thought of Illumi stammering, confronted by their parents about why he’d been unable to control himself, only a few needles away from his body bearing the full story of how Killua had fucked him.

Killua finally untangled his tingling foot, pushed Illumi’s shoulders into the bed and climbed onto his chest. “Unless you go another round with me.”

Illumi blinked, eyelids weighing a thousand pounds as he looked up at Killua’s erection. “Killu, I’m tired—”

“ _Huh_?” Killua slid back on Illumi’s body like climbing down a pole, down past his flaccid penis, and wedged himself in between Illumi’s long legs. “You want me to fuck a pervert like that instead? You have to take care of your little brother, Illumi.” He bit a piece of pale thigh that hadn’t yet been marked. He wouldn’t leave any places of purity left, even though Illumi would still think himself a paragon. “Save me from my own bad actions—that’s always been your goal, right?”

Illumi reached over to his nightstand, revealing the bruises and bitemarks on the underside of his arm and picked up the bottle of lube. _Oh to see him so resigned and unwilling_ —for once not the pursuer but the bitch. Killua could hardly contain himself. Did Illumi really think he was saving Killua from fucking Hisoka, or was he trying to shut him up and make him happy?

Illumi tried to roll over underneath him, clearly planning to sleep on his stomach while Killua had his way, but Killua pressed roughly on his hipbones and pried the lube from those slender fingers. He wanted to see Illumi’s face, even if he did fall asleep.

At this rate, they’d never make it out of bed, but Killua couldn’t help himself as he inserted his fingers into Illumi’s ass roughly. Still loose from having done it only a few hours ago and probably still stuffed with Killua’s cum. That was even more arousing somehow; Killua grabbed Illumi’s legs and pushed them forward until his knees were level with his shoulders. His spine and legs bent easily as always. “Let’s see you try to fall asleep like this,” Killua whispered to himself more than anyone because Illumi’s eyes were still closed. Killua had to stand on shaky legs, the bed creaking from the sudden weight, to put himself into Illumi.

The night air always absorbed noise better than the morning sun, so the sounds of Killua slapping into Illumi were loud, reverberating off the walls of the room. There was no second person moaning or moving, so Killua was left listening only to his own voice and thrusts. He raked his nails on the exposed undersides of Illumi’s thighs, watching the bright red welts break out as he quickened his thrust. He panted Illumi’s name, but Illumi didn’t open his eyes, sprawled out and twisted like a broken doll.

Maybe if Killua busted him up enough Illumi’s needles would miss covering a mark or two. How many needles would he need to push under his skin to get rid of all of these marks every single day until they healed up? Killua could come home more often and cause Illumi to slip up. Reopen the marks before they had the chance to heal. Having needles in his body every waking hour and while on jobs would cause him to get caught by their father eventually. The good son, marked up like a whore.

“Illumi—” He was getting close. “Illumi, wake up—” Illumi couldn’t be asleep when he came. He wanted to look into those dead eyes instead of the patchwork field that was his skin. He slapped Illumi’s thigh, hoping it would somehow wake him up even though clawing and drawing blood hadn’t. 

Nothing.

Killua leaned in awkwardly, still balls-deep, and reach through Illumi’s legs to touch his face. How was he sleeping while getting his ass pounded like this, his legs suspended in mid-air and his lower back curved in on himself? He really did seem inhuman sometimes.

At the brush of Killua’s fingertips on his cheek Illumi’s eyes fluttered open, the haze of his ripped-away dreams making them glassy. “Killu?” He looked at his own legs around his face and Killua sweating over him, a small smile blooming on his lips. As if anyone would smile while waking up in a situation like this.

“Look at me—Illumi—I’m going to come in you.”

He nodded dumbly, watching Killua as if waiting for some impressive show.

“You idiot—you— _ah_ , you absolute whore—” Killua grabbed the back of Illumi’s legs, embedding his nails in the tops of those pale white thighs like pins. That got a small noise out of Illumi—not because it hurt, but because watching Killua was doing something to him, even while half-asleep. That noise drove him to come a moment later, gripping those thighs like they were the last lifeline keeping him on the planet. Otherwise he’d be hurtling towards outer space, unable to breathe or come back down to solid ground.

He dropped Illumi’s body and his own, letting both fall on the bed with a final creak and thud. He laid between Illumi’s parted legs, probably squishing his junk uncomfortably—but Illumi didn’t complain. Eventually, Killua unstuck his sweaty self from Illumi’s skin and crawled up next to him. He was a bit more awake now, a little hard after that display, and his eyes refused to leave Killua, as if studying a wild specimen for the first time. “I’m not getting you off,” Killua said. “You slept through that opportunity.”

Illumi sat up in slow-motion, either from ache or exhaustion, and laid chest to chest on him with his full weight. Killua could feel the uncomfortable crust of blood against his chest and wondered if he’d gone a bit too far this time. Illumi wasn’t immune to pain, especially not something as internal as his insides getting jostled with his lower back bent at a strange angle. The bags under his eyes were heavy and he looked as though he were in another world—not too surprising, consider he’d been woken up with a dick in him.

Illumi didn’t say anything, his hair creating a dark curtain around them as he leaned over Killua’s face, noses touching. He didn't usually get this close. Killua’s eyes closed and he felt cold lips pressing against his open mouth—the shock of which left him dumbfounded for a second—a second too long to be locked in this kiss—before he pushed Illumi away. “What the fuck are you doing? You can’t just—”

Illumi blinked at him, unaffected by being shoved away. There was no shame or anger from being rejected, or even a look of regret. Illumi retreated quickly, hair whipping behind him as he laid back down and pulled one of the messy sheets up to cover his naked body. Killua was the one reeling, wondering what had gotten into Illumi to try to kiss him like that. Never in the history of the things they’d done had they kissed or even come close. “You’re too tired to be in your right mind.” Killua raised himself from the bed, his nerves so riled up after that strange encounter that he no longer felt sleepy. “I’ll see you later at Kalluto’s party.”

As much as he liked to sleep in Illumi’s bed in the aftermath he didn’t think he could sleep—let alone sleep in the same bed. He started looking for his underwear, realizing what a mess he’d made in Illumi’s room the night before. When Killua got a fire in his stomach like he had the night before he liked to tear through Illumi’s possessions like a feline in heat. Now with ripped shreds of Illumi’s clothes, a jewelry box and its contents, a cluster of CDs and their busted cases, and other litter strewn across the floor, Killua had to give up looking for his underwear. He grabbed his pants instead and slipped them up without underwear. He found his shirt, but it was in tatters too, so he left it on the floor with everything else.

Surprisingly, Illumi was fast asleep. He'd never trusted Killua enough to fall asleep around him, but now that Killua was older and could really do some damage—now he trusted him? Or maybe he was just so paralyzed with exhaustion that he didn’t have a choice. Killua hadn’t bothered to ask what his long job had been, how it had gone, or how strung-out he already was. He could have been awake for weeks already. Maybe that was what the kiss was about too—he was so tired that he was delusional and impulsive.

Killua cracked open the door; one of the butlers had moved Illumi’s overnight bag out from the middle of the hallway and placed it right outside the door along with the gift for Kalluto that Killua had dropped. Some of the butlers had to already know about them—there was no way they didn’t and hadn’t known for years. Killua wondered what kind of hush money Illumi was paying them and if his moans ever reached their ears. He brought Illumi’s bag inside and dropped it on the rest of the mess.

But if it was an impulsive decision made from sleep deprivation, why hadn’t Illumi looked as though he regretted it? 

Killua sighed, walking shirtless out of his brother’s room for the hundredth time in his life. The smells, temperature, and even humidity of the air changed when he walked out into the hallway, and he felt disconnected from the world he’d just exited. When would he stop being tempted back in? He was hobbling through his childhood home, totally spent and bearing a humiliating timeline of sex on his body. He’d have to borrow some makeup from Kalluto just to be presentable around his parents, which was agonizing. But part of him knew he’d end up in the same situation the next time he visited.

When Illumi finally made it to Kalluto’s party, he acted as though nothing had happened between them. It was much easier for him than Killua—who kept tracing his eyes over every patch of visible skin. He wondered if Illumi had showered out what Killua had buried deep in him or if he was still walking around with all signs of blood and sex covered by his needles. At least now he looked well-rested.

“Killu,” Illumi said when there was a lull in the party where Kalluto was admiring all of his gifts. Illumi walked into the dim hall and Killua followed calmly, making sure no one could see them leaving in succession. Out in the hall, there were the muffled sounds of laughter and murmuring, like they were far away from the world that the rest of their family lived in. Or maybe that was the weight of their shared secrets.

“I sure hope you aren’t dragging me out here for a quickie, I told you that boat already sailed—” Killua whispered, swallowing the rest of his sentence as Illumi started to unbutton his shirt. “Are you listening? Hey, wait—”

But Illumi stopped after the third button, revealing the large claw mark Killua had left across his chest—swollen and winding, like a bloated snake on its back.

**Author's Note:**

> This is an experimental piece for me, much different than my style for Damage x Control, and self-indulgent, but I hope it was enjoyable! 
> 
> Please feel free to tell me what you thought, and to ask me any questions! ♥‿♥
> 
> Love,  
> Brocon


End file.
